In general, multi-function tools, including in a single instrument, pliers, and other selected tools, such as screwdrivers, knife blades, files and the like, are well known. The prior art multi-function tools typically include a cross-jaw plier with channel-shaped handles connected to the shanks or tangs of the respective plier jaws. In one type of multi-function tool, the cross-jaw pliers are pivotally mounted to the handles at the distal end, the jaws being adapted to nest within the handle for storage. Examples of such multiple tools are described in U.S. Pat. Nos. 4,238,862, 4,744,272 and 4,888,869 issued on Dec. 16, 1980, May 17, 1988 and Dec. 26, 1989, respectively, to Timothy S. Leatherman.
In another type of multi-function tool, the tangs of the respective plier jaws are slidably affixed to the respective handles such that the jaws can be slidably retracted into the interior of the handle channels. Examples of such multi-function tools are described in U.S. Pat. Nos. 5,142,721 and 5,212,844 issued on Sep. 1, 1992 and May 25, 1993, respectively, to Sessions et al. These patents are incorporated herein by reference.
The plier jaws of the multi-function tools identified above are mechanically attached to the handles such that assembly of the plier jaws to the handles or removal of the plier jaws requires the use of a separate tool. The use of a separate tool inhibits the user from easily removing the plier jaws and the mechanical attachment of the jaws to the handles increases manufacturing costs.
It is therefore desirable to provide a multi-function tool in which the tool can be easily attached and removed from the handles without the use of a separate tool. Additionally, it is desirable to provide a handle engagement mechanism on the tool to positively lock the tool into engagement with the handles. Finally, it is also desirable to provide an interlocking mechanism to easily interchange handles, thereby allowing access to a larger variety of tools contained in different handle assemblies.